I imagine most Linux users will be on either KDE or GNOME+Mutter. People who don't use that are likely to be into low-spec desktop environments (XFCE and such) or niche solutions (i3 and friends).
There are niche stack window managers (labwc/Liri shell/Wayfire) but they don't have quite the cult following tiling WMs do.
X window managers are a lot simpler than Wayland compositors, even including helper libraries, so I expect this to remain true.
There's a lot more small and obscure tiling WMs than stacking ones for X11 as well.
That's not really true, though; AFAIK KDE/GNOME don't implement tabbed windows or the ability to stick them together.
PS: I am not affiliated with the repo in anyway, but think that scrollable-tiling should be better known.
Vision Pro or its copies are unlikely to be unlocked enough to run user supplied linux.
The Vision Pro concept is hardly new, of course, and there are already various window managers that will work with existing VR headsets. All someone needs to do is bring out a portable PC with the right form factor. I imagine taking the controllers and the touch screen off a Steam Deck would make for something you could quite comfortably wear, though you'd want a better battery/power plug design than what Apple has in mind.
Another benefit is how sick it looks (In my opinion). Anyone looking would be interested.
And then I use workspaces for different groups of windows, i.e. messaging apps, the browser, and different projects all go on different workspaces.
I use xmonad so I'm well used to tiling, I just don't get why you would want to have a view into only half of a window.
There are preset widths (by default: ~33%, 50%, ~67%) which you can toggle between with a key, plus a 100% "maximized" width that you can toggle separately. This works out pretty well from my experience and gives you the convenient 33/67 and 50/50 layouts (or 33/33/33 on ultrawides).
The initial window width is what the window wants. So the window is free to use any size on creation, then PaperWM expands it to full height with the same width that the window had selected.